U.S. patent application number 15/440075 was filed with the patent office on 2017-08-31 for light signal multiplexer and light signal demultiplexer.
The applicant listed for this patent is ELECTRONICS AND TECNOLOGY RESEARCH INSTITUTE. Invention is credited to Joon Young HUH, Sae Kyoung KANG, Jie Hyun LEE, Jun Ki LEE.
Application Number | 20170250773 15/440075 |
Document ID | / |
Family ID | 59679893 |
Filed Date | 2017-08-31 |
United States Patent
Application |
20170250773 |
Kind Code |
A1 |
HUH; Joon Young ; et
al. |
August 31, 2017 |
LIGHT SIGNAL MULTIPLEXER AND LIGHT SIGNAL DEMULTIPLEXER
Abstract
A light signal multiplexer and a light signal demultiplexer
corresponding to the light signal multiplexer. The light signal
multiplexer may include a reflector and a filter, in which the
reflector is disposed on a plurality of input light paths to allow
a plurality of light signals input along the input light paths to
be reflected toward the filter disposed on at least one output
light path, and the filter is disposed to allow the light signals
reflected toward the filter to be reflected along the at least one
output light path, and thus the light signal multiplexer may
individually set the input light paths for the light signals.
Inventors: |
HUH; Joon Young; (Daejeon,
KR) ; KANG; Sae Kyoung; (Daejeon, KR) ; LEE;
Jun Ki; (Daejeon, KR) ; LEE; Jie Hyun;
(Daejeon, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ELECTRONICS AND TECNOLOGY RESEARCH INSTITUTE |
Daejeon |
|
KR |
|
|
Family ID: |
59679893 |
Appl. No.: |
15/440075 |
Filed: |
February 23, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 27/1006 20130101;
H04J 14/0256 20130101; G02B 6/29386 20130101; G02B 6/29362
20130101; G02B 27/14 20130101; G02B 6/2938 20130101; H04J 14/02
20130101 |
International
Class: |
H04J 14/02 20060101
H04J014/02; G02B 27/14 20060101 G02B027/14; G02B 27/10 20060101
G02B027/10 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 26, 2016 |
KR |
10-2016-0023592 |
Claims
1. A light signal multiplexer comprising: a reflector; and a
filter, wherein the reflector is disposed on a plurality of input
light paths to allow a plurality of light signals input along the
plurality of input light paths to be reflected toward the filter
disposed on at least one output light path, and the filter is
disposed to allow the light signals reflected toward the filter to
be reflected along the at least one output light path, wherein the
at least one output light path corresponds to at least one of the
plurality of input light paths.
2. The light signal multiplexer of claim 1, wherein the reflector
is parallel to the filter corresponding to the reflector.
3. The light signal multiplexer of claim 1, wherein a length from
the plurality of input light paths to the at least one output light
path is determined based on at least one of a distance between the
reflector and the filter and an angle between the reflector and the
plurality of input light paths.
4. The light signal multiplexer of claim 1, wherein the plurality
of light signals have different wavelengths.
5. A light signal multiplexer comprising: a reflector; and a
filter, wherein the reflector is disposed on a plurality of input
light paths to allow a plurality of light signals input along the
plurality of input light paths to be reflected toward the filter
disposed on at least one output light path, and the filter is
disposed to allow the light signals reflected toward the filter to
be reflected along the at least one output light path, wherein the
at least one output light path does not correspond to the plurality
of input light paths.
6. The light signal multiplexer of claim 5, wherein the reflector
is parallel to the filter corresponding to the reflector.
7. The light signal multiplexer of claim 5, wherein a length from
the plurality of input light paths to the at least one output light
path is determined based on at least one of a distance between the
reflector and the filter and an angle between the reflector and the
plurality of input light paths.
8. The light signal multiplexer of claim 5, wherein the plurality
of light signals have different wavelengths.
9. A light signal demultiplexer comprising: a reflector; and a
filter, wherein the filter is disposed on at least one input light
path to allow at least one light signal input along the at least
one input light path to be reflected toward the reflector disposed
on a plurality of output light paths, and the reflector is disposed
to allow the light signal reflected toward the reflector to be
reflected along the plurality of output light paths, wherein at
least one of the plurality of output light paths corresponds to the
at least one input light path.
10. The light signal demultiplexer of claim 9, wherein the
reflector is parallel to the filter corresponding to the
reflector.
11. The light signal demultiplexer of claim 9, wherein a length
from the at least one input light path to the plurality of output
light paths is determined based on at least one of a distance
between the reflector and the filter and an angle between the
reflector and the plurality of output light paths.
12. The light signal demultiplexer of claim 9, wherein light
signals to be output along the plurality of output light paths have
different wavelengths.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the priority benefit of Korean
Patent Application No. 10-2016-0023592 filed on Feb. 26, 2016, in
the Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference for all purposes.
BACKGROUND
[0002] 1. Field
[0003] One or more example embodiments relate to an optical
communication device, and more particularly, to a device for
multiplexing a plurality of light signals or demultiplexing the
multiplexed light signals.
[0004] 2. Description of Related Art
[0005] An optical communication device may generate a light signal
based on an electrical signal, or generate an electrical signal
based on a received light signal. Due to a rapid increase in
traffic, an optical communication device having a higher
transmission capacity is being developed.
[0006] A representative method of increasing a transmission
capacity of an optical communication device may include a
wavelength-division multiplexing (WDM) method. The WDM method may
multiplex a plurality of light signals having different wavelengths
onto a single optical fiber, and transmit the multiplexed light
signals. The WDM method may be widely applied to a short-distance
optical transport network (OTN), such as, for example, Ethernet, in
addition to a medium- and long-distance OTN.
[0007] A light signal multiplexer may multiplex a plurality of
light signals having different wavelengths onto a single optical
fiber. The light signal multiplexer may multiplex the light signals
using, for example, a method using an arrayed waveguide grating
(AWG) and a bulk optics method using a thin film filter.
[0008] The bulk optics method may have a low insertion loss and a
large alignment margin. However, when the number of light signals
targeted for multiplexing increases, a length of a light path of a
light signal may increase rapidly. In addition, the light path may
be fixed, and thus a start point of the light signal may need to be
accurately controlled because the accurate control of the start
point may affect a yield of the light signal multiplexer.
SUMMARY
[0009] An aspect provides a light signal multiplexer and a light
signal demultiplexer that may individually set light paths to
reduce a length of the light paths despite an increase in the
number of light signals, and thus may have a lower insertion
loss.
[0010] According to an aspect, there is provided a light signal
multiplexer including a reflector and a filter. The reflector may
be disposed on a plurality of input light paths to allow a
plurality of light signals input along the plurality of input light
paths to be reflected toward the filter disposed on at least one
output light path. The filter may be disposed to allow the light
signals reflected toward the filter to be reflected along the at
least one output light path. The at least one output light path may
correspond to at least one of the plurality of input light
paths.
[0011] The reflector may be parallel to the filter corresponding to
the reflector.
[0012] A length from the plurality of input light paths to the at
least one output light path may be determined based on at least one
of a distance between the reflector and the filter and an angle
between the reflector and the plurality of input light paths.
[0013] The plurality of light signals may have different
wavelengths.
[0014] According to another aspect, there is provided a light
signal multiplexer including reflector and a filter. The reflector
may be disposed on a plurality of input light paths to allow a
plurality of light signals input along the plurality of input light
paths to be reflected toward the filter disposed on at least one
output light path. The filter may be disposed to allow the light
signals reflected toward the filter to be reflected along the at
least one output light path. The at least one output light path may
not correspond to the plurality of input light paths.
[0015] The reflector may be parallel to the filter corresponding to
the reflector.
[0016] A length from the plurality of input light paths to the at
least one output light path may be determined based on at least one
of a distance between the reflector and the filter and an angle
between the reflector and the plurality of input light paths.
[0017] The plurality of light signals may have different
wavelengths.
[0018] According to still another aspect, there is provided a light
signal demultiplexer including a reflector and a filter. The filter
may be disposed on at least one input light path to allow at least
one light signal input along the at least one input light path to
be reflected toward the reflector disposed on a plurality of output
light paths. The reflector may be disposed to allow the light
signal reflected toward the reflector to be reflected along the
plurality of output light paths. At least one of the plurality of
output light paths may correspond to the at least one input light
path.
[0019] The reflector may be parallel to the filter corresponding to
the reflector.
[0020] A length from the at least one input light path to the
plurality of output light paths may be determined based on at least
one of a distance between the reflector and the filter and an angle
between the reflector and the plurality of output light paths.
[0021] Light signals to be output along the plurality of output
light paths may have different wavelengths.
[0022] According to yet another aspect, there is provided a light
signal demultiplexer including a reflector and a filter. The filter
may be disposed on at least one input light path to allow at least
one light signal input along the at least one input light path to
be reflected toward the reflector disposed on a plurality of output
light paths. The reflector may be disposed to allow the light
signal reflected toward the reflector to be reflected along the
plurality of output light paths. At least one of the plurality of
output light paths may not correspond to the at least one input
light path.
[0023] The reflector may be parallel to the filter corresponding to
the reflector.
[0024] A length from the at least one input light path to the
plurality of output light paths may be determined based on at least
one of a distance between the reflector and the filter and an angle
between the reflector and the plurality of output light paths.
[0025] Light signals to be output along the plurality of output
light paths may have different wavelengths.
[0026] According to example embodiments, the light signal
multiplexer and the light signal demultiplexer described herein may
individually set light paths to reduce a length of the light paths
and also have a lower insertion loss, despite an increase in the
number of light signals.
[0027] Additional aspects of example embodiments will be set forth
in part in the description which follows and, in part, will be
apparent from the description, or may be learned by practice of the
disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] These and/or other aspects, features, and advantages of the
present disclosure will become apparent and more readily
appreciated from the following description of example embodiments,
taken in conjunction with the accompanying drawings of which:
[0029] FIG. 1 is a diagram illustrating a structure of a light
signal multiplexer according to an example embodiment;
[0030] FIG. 2 is a diagram illustrating a structure of a light
signal multiplexer in which an output light path of the light
signal multiplexer corresponds to at least one of a plurality of
input light paths according to an example embodiment;
[0031] FIG. 3 is a diagram illustrating a structure of a reflector
and a structure of a filter of a light signal multiplexer according
to an example embodiment;
[0032] FIG. 4 is a diagram illustrating a structure of a light
signal multiplexer in which a light path adjuster is disposed on
each of a plurality of input light paths according to an example
embodiment;
[0033] FIGS. 5A and 5B are diagrams illustrating a structure of a
light signal multiplexer in which an output light path does not
correspond to an input light path according to an example
embodiment;
[0034] FIG. 6 is a diagram illustrating a structure of a light
signal demultiplexer according to an example embodiment; and
[0035] FIG. 7 is a diagram illustrating a structure of a light
signal demultiplexer in which an output light path does not
correspond to an input light path according to an example
embodiment.
DETAILED DESCRIPTION
[0036] Hereinafter, some example embodiments will be described in
detail with reference to the accompanying drawings. Regarding the
reference numerals assigned to the elements in the drawings, it
should be noted that the same elements will be designated by the
same reference numerals, wherever possible, even though they are
shown in different drawings. Also, in the description of
embodiments, detailed description of well-known related structures
or functions will be omitted when it is deemed that such
description will cause ambiguous interpretation of the present
disclosure.
[0037] Various alterations and modifications may be made to the
examples. Here, the examples are not construed as limited to the
disclosure and should be understood to include all changes,
equivalents, and replacements within the idea and the technical
scope of the disclosure.
[0038] Terms such as first, second, A, B, (a), (b), and the like
may be used herein to describe components. Each of these
terminologies is not used to define an essence, order or sequence
of a corresponding component but used merely to distinguish the
corresponding component from other component(s). For example, a
first component may be referred to a second component, and
similarly the second component may also be referred to as the first
component.
[0039] It should be noted that if it is described in the
specification that one component is "connected," "coupled," or
"joined" to another component, a third component may be
"connected," "coupled," and "joined" between the first and second
components, although the first component may be directly connected,
coupled or joined to the second component. In addition, it should
be noted that if it is described in the specification that one
component is "directly connected" or "directly joined" to another
component, a third component may not be present therebetween.
Likewise, expressions, for example, "between" and "immediately
between" and "adjacent to" and "immediately adjacent to" may also
be construed as described in the foregoing.
[0040] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting. As
used herein, the singular forms "a," "an," and "the," are intended
to include the plural forms as well, unless the context clearly
indicates otherwise. It will be further understood that the terms
"comprises," "comprising," "includes," and/or "including," when
used herein, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
[0041] Unless otherwise defined, all terms, including technical and
scientific terms, used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
disclosure pertains. Terms, such as those defined in commonly used
dictionaries, are to be interpreted as having a meaning that is
consistent with their meaning in the context of the relevant art,
and are not to be interpreted in an idealized or overly formal
sense unless expressly so defined herein.
[0042] Hereinafter, examples are described in detail with reference
to the accompanying drawings. Like reference numerals in the
drawings denote like elements, and a known function or
configuration will be omitted herein.
[0043] FIG. 1 is a diagram illustrating a structure of a light
signal multiplexer 100 according to an example embodiment.
[0044] Referring to FIG. 1, a plurality of input light paths
includes a first input light path 101, a second input light path
102, a third input light path 103, and a fourth input light path
104. A plurality of light signals input to the light signal
multiplexer 100 may proceed along different input light paths. The
light signals input to the light signal multiplexer 100 may have
different wavelengths.
[0045] The light signal multiplexer 100 may set, to be an output
light path, at least one among the input light paths 101, 102, 103,
and 104. The light signal multiplexer 100 may output a multiplexed
light signal through the third input light path 103. Although the
light signal multiplexer 100 illustrated in FIG. 1 sets only the
third input light path 103 to be the output light path, the light
signal multiplexer 100 may have two or more output light paths.
That is, at least one output light path of the light signal
multiplexer 100 may correspond to at least one among the input
light paths.
[0046] Referring to FIG. 1, the light signal multiplexer 100
includes a plurality of reflectors, which are illustrated as black
boxes, for example, a first reflector 111, a second reflector 112,
and a third reflector 113. Here, a reflector may be disposed on an
input light path. In addition, the light signal multiplexer 100
also includes a plurality of filters, which are illustrated as
latticed boxes, for example, a first filter 121, a second filter
122, and a third filter 123 that correspond to the reflectors 111,
112, and 113, respectively. In the drawings provided hereinafter, a
black box indicates a reflector, and a latticed box indicates a
filter.
[0047] Here, a filter may be disposed on an output light path. A
reflector may be disposed to allow a light signal that is input
along an input light path to be reflected toward a filter
corresponding to the reflector, and the filter may be disposed to
allow the light signal that is reflected toward the filter to be
reflected along the output light path.
[0048] As illustrated in FIG. 1, a first light signal that is input
along the first input light path 101 may reach the first reflector
111. The first reflector 111 may be disposed on the first input
light path 101, and disposed to allow the first light signal to be
reflected toward the first filter 121 corresponding to the first
reflector 111. The first reflector 111 may be inclined at a preset
angle against the first input light path 101. Here, a reflector may
include a material that may reflect a light signal.
[0049] The first light signal may proceed to the first filter 121
by the first reflector 111. Here, a filter may be a thin film
filter, and may reflect a light signal reaching the filter or pass
the light signal to pass through based on a wavelength.
[0050] For example, the first filter 121 may reflect only a light
signal having the same wavelength as the first light signal, and
allow a light signal having a wavelength different from the
wavelength of the first light signal to pass through. The first
filter 121 may reflect the first light signal along the output
light path. Although the first filter 121 is disposed on the third
input light path 103, the third input light path 103 may not be
affected by the first filter 121 because a light signal that is
input along the third input light path 103 has a wavelength
different from the wavelength of the first light signal.
[0051] The first filter 121 may be disposed to allow the first
light signal to be reflected along the output light path. Thus, the
first filter 121 may be inclined at a preset angle against the
output light path. Although the disposition of the first reflector
111 and the first filter 121 is described herein, the second
reflector 112 and the third reflector 113, and the second filter
122 and the third filter 123 may be also disposed in a similar way
of the first reflector 111 and the first filter 121 being disposed.
Thus, a plurality of light signals that are input along the first
input light path 101 through the fourth input light path 104 may be
multiplexed onto the single output light path.
[0052] As illustrated in FIG. 1, the light signal multiplexer 100
may multiplex four light signals. Each of the light signals may be
four 25 gigabits per second (Gbps) light signals having different
wavelengths in accordance with a 100GBASE-LR4 standard. The
multiplexed light signals may proceed along the output light path,
and be output through a single mode optical fiber 130. Although an
example of multiplexing four light signals is described with
reference to FIG. 1, the light signal multiplexer 100 may multiplex
two or three light signals, and also five or more light
signals.
[0053] According to an example embodiment, the light signal
multiplexer 100 may set light paths, independently, each of the
light paths using a separate reflector and filter. When the light
paths are independently set, a length of each light path may not
increase despite an increase in the number of light signals to be
multiplexed. Thus, an insertion loss of a light signal may be
reduced. Further, the light signal multiplexer 100 may be more
readily manufactured because a start point of a light signal does
not need to be precisely controlled.
[0054] According to an example embodiment, the light signal
multiplexer 100 may set two or more output light paths. For
example, the light signal multiplexer 100 may set the second input
light path 102 to be the output light path, in addition to the
third input light path 103. In such an example, light signals that
are input along the second input light path 102 and the third input
light path 103 may not need an additional reflector or filter, and
thus only a reflector and filter for light signals that are input
along the first input light path 101 and the fourth input light
path 104 may be disposed.
[0055] Although the third input light path 103 is set to be the
output light path in FIG. 1, the light signal multiplexer 100 may
set another input light path to be the output light path.
[0056] FIG. 2 is a diagram illustrating a structure of a light
signal multiplexer 200 in which an output light path of the light
signal multiplexer 200 corresponds to at least one of a plurality
of input light paths according to an example embodiment. Referring
to FIG. 2, the light signal multiplexer 200 may set, to be an
output light path, a fourth input light path 240 disposed at a
rightmost side among a plurality of input light paths, for example,
a first input light path 210, a second input light path 220, a
third input light path 230, and the fourth input light path
240.
[0057] The output light path of the light signal multiplexer 200
may be flexibly set based on a characteristic of each of the input
light paths 210, 220, 230, and 240. The light signal multiplexer
200 may set the fourth input light path 240 to be the output light
path because a light signal that is input along the fourth input
light path 240 may be more rapidly attenuated compared to other
light signals that are input along the other input light paths 210,
220, and 230.
[0058] FIG. 3 is a diagram illustrating a structure of a reflector
330 and a structure of a filter 340 of a light signal multiplexer
according to an example embodiment.
[0059] Referring to FIG. 3, the light signal multiplexer includes
the reflector 330 and the filter 340 corresponding to the reflector
330. The reflector 330 may be disposed on an input light path 310,
and the filter 340 may be disposed on an output light path 320.
[0060] The reflector 330 may be disposed to allow a light signal
that is input along the input light path 310 to be reflected toward
the filter 340. The filter 340 may be disposed to allow the light
signal that is reflected toward the filter 340 to be reflected
along the output light path 320. Thus, when the input light path
310 and the output light path 320 are parallel to each other, the
reflector 330 and the filter 340 may also be parallel to each
other.
[0061] As illustrated in FIG. 3, an angle formed between the filter
340 and the output light path 320 may correspond to an angle
.THETA. formed between the reflector 330 and the input light path
310. In such a case, the reflector 330 and the filter 340 may
reflect the light signal at a reflection angle identical to an
incident angle. An angle to be formed between the input light path
310 and a light path reflected from the reflector 330 may be a
double of the angle .THETA., for example, 2.times..THETA.. Using a
trigonometric function, a relationship between a length L 350 from
the input light path 310 to the output light path 320 and a
distance d 360 between the reflector 330 and the filter 340 may be
derived as represented by Equation 1 below.
L=d.times.sin(2 .THETA.) [Equation 1]
[0062] Based on Equation 1, the light signal multiplexer may
accurately dispose the reflector 330 and the filter 340 that are
disposed on a plurality of light paths. Further, the plurality of
light paths may be set independently from one another, and thus the
light signal multiplexer may be more readily manufactured.
[0063] According to an example embodiment, using such a
relationship between the reflector 330 and the filter 340, a light
path adjuster including the reflector 330 and the filter 340 as one
set may be provided.
[0064] FIG. 4 is a diagram illustrating a structure of a light
signal multiplexer 400 in which a light path adjuster is disposed
on each of a plurality of input light paths according to an example
embodiment.
[0065] Referring to FIG. 4, a plurality of light path adjusters,
for example, a light path adjuster 410, a light path adjuster 420,
and a light path adjuster 430, may include a reflector and a
filter. Here, the reflector and the filter may be parallel to each
other. Each of the light path adjusters 410, 420, and 430 may be
disposed to allow the reflector to be disposed on an input light
path, and the filter to be disposed on an output light path. A
length of each of the light path adjusters 410, 420, and 430 may be
set based on Equation 1.
[0066] FIGS. 5A and 5B are diagrams illustrating a structure of a
light signal multiplexer 500 in which an output light path does not
correspond to an input light path according to an example
embodiment.
[0067] According to an example embodiment, at least one output
light path of the light signal multiplexer 500 may not correspond
to a plurality of input light paths. The at least one output light
path of the light signal multiplexer 500 may be configured
independently from the plurality of input light paths. Referring to
FIGS. 5A and 5B, an output light path 550 or 551 may not correspond
to a first input light path 510, a second input light path 520, a
third input light path 530, or a fourth input light path 540.
[0068] Referring to FIG. 5A, the output light path 550 may be set
to be in the middle of the first input light path 510, the second
input light path 520, the third input light path 530, and the
fourth input light path 540. Thus, a deviation in lengths of the
input light paths 510, 520, 530, and 540 of the light signal
multiplexer 500 may be minimized.
[0069] Also, the output light path 550 may be set in another space
among the input light paths 510, 520, 530, and 540, instead of
being in the middle of the input light paths 510, 520, 530, and
540. For example, the output light path 550 may be set in a space
between the first input light path 510 and the second input light
path 520, or in a space between the third input light path 530 and
the fourth input light path 540.
[0070] Alternatively, the output light path 550 may be set in
another space that is not among the input light paths 510, 520,
530, and 540. For example, referring to FIG. 5B, the output light
path 551 may be set outside the input light paths 510, 520, 530,
and 540. Thus, an output light path may be set at various
locations, and the light signal multiplexer 500 may be more
unrestrictedly designed.
[0071] According to an example embodiment, in addition to a light
signal multiplexer that may individually set and adjust light paths
for light signals having different wavelengths, a light signal
demultiplexer that may individually set and adjust light paths for
light signals having different wavelengths may be provided.
[0072] FIG. 6 is a diagram illustrating a structure of a light
signal demultiplexer 600 according to an example embodiment.
[0073] Referring to FIG. 6, a plurality of output light paths
includes a first output light path 601, a second output light path
602, a third output light path 603, and a fourth output light path
604. At least one light signal that is input to the light signal
demultiplexer 600 may be demultiplexed along the different output
light paths 601, 602, 603, and 604. The light signal input to the
light signal demultiplexer 600 may be a multiplexed light signal
including a plurality of light signals having different
wavelengths.
[0074] The light signal demultiplexer 600 may set, to be an input
light path, at least one of the output light paths 601, 602, 603,
and 604. As illustrated in FIG. 6, the input light path may
correspond to the second output light path 602. Although the light
signal demultiplexer 600 sets one of the output light paths 601,
602, 603, and 604 to be the input light path in FIG. 6, the light
signal demultiplexer 600 may have at least one input light path.
That is, the at least one input light path of the light signal
demultiplexer 600 may correspond to at least one of a plurality of
output light paths.
[0075] As illustrated in FIG. 6, the light signal demultiplexer 600
includes a plurality of reflectors, for example, a first reflector
611, a second reflector 612, and a third reflector 613. Here, a
reflector may be disposed on an output light path. The light signal
demultiplexer 600 also includes a plurality of filters, for example
a first filter 621, a second filter 622, and a third filter 623.
Here, a filter may be disposed on an input light path, and disposed
to allow a light signal that is input along an input light path to
be reflected toward a corresponding reflector. The reflector may be
disposed to allow the light signal that is reflected toward the
reflector to be reflected along an output light path.
[0076] In detail, a first light signal that is input along the
second output light path 602, which is set to be the input light
path, may reach the first filter 621. The first filter 621 may be
disposed on the input light path, and disposed to allow the first
light signal to be reflected toward the first reflector 611
corresponding to the first filter 621. Thus, the first filter 621
may be inclined at a preset angle against the second output light
path 602.
[0077] Here, a filter may be a thin film filter. In addition, the
filter may reflect a light signal reaching the filter or allow the
light signal to pass through based on a wavelength. For example,
the first filter 621 may reflect only a light signal having a
wavelength identical to a wavelength of the first light signal, and
allow a light signal having a wavelength different from the
wavelength of the first light signal to pass through. The first
filter 621 may reflect the first light signal toward the first
reflector 611. In addition, the first filter 621 may allow the
light signal having the different wavelength to pass through,
excluding the first light signal.
[0078] Thus, each of the filters 621, 622, and 623 that are
disposed in order on the input light path may reflect only a light
signal having a wavelength corresponding to each of the filters
621, 622, and 623 toward a corresponding reflector. That is, each
of the filters 621, 622, and 623 may extract only a light signal
having a wavelength corresponding to each of the filters 621, 622,
and 623. Thus, a multiplexed light signal including a plurality of
light signals having different wavelengths may be
demultiplexed.
[0079] The first light signal may proceed to the first reflector
611 by the first filter 621. Here, a reflector may include a
material that may reflect a light signal. The first reflector 611
may be disposed to allow the first light signal to be reflected
along the first output light path 601. Thus, the first reflector
611 may be inclined at a preset angle against the first output
light path 601.
[0080] Although the disposition of the first reflector 611 and the
first filter 621 is described herein, the second reflector 612 and
the third reflector 613, and the second filter 622 and the third
filter 623 may be also disposed in a similar way of the first
reflector 611 and the first filter 621 being disposed. A distance
between each reflector and a corresponding filter and the preset
angle may be determined based on Equation 1.
[0081] The light signal demultiplexer 600 may include a plurality
of light path adjusters including a reflector and a filter
corresponding to the reflector. For example, the light signal
demultiplexer 600 may include a first light path adjuster including
the first reflector 611 and the first filter 621 corresponding to
the first reflector 611, a second light path adjuster including the
second reflector 612 and the second filter 622 corresponding to the
second reflector 612, and a third light path adjuster including the
third reflector 613 and the third filter 623 corresponding to the
third reflector 613. A length of each light path adjuster and an
angle formed between each light path adjuster and the input light
path may be determined based on Equation 1.
[0082] Referring to FIG. 6, the light signal demultiplexer 600 may
demultiplex a light signal having four different wavelengths that
proceeds along one light path. Each light signal may be four 25
Gbps light signals having the different wavelengths in accordance
with a 100GBASE-LR4 standard. Although an example of the light
signal demultiplexer 600 configured to demultiplex four light
signals is described with reference to FIG. 6, the light signal
demultiplexer 600 may demultiplex two or three light signals, and
also five or more light signals.
[0083] According to an example embodiment, the light signal
demultiplexer 600 may set light paths independently, each using a
separate reflector and filter. When the light paths are set
independently from one another, a length of each light path may not
increase despite an increase in the number of light signals to be
demultiplexed. Thus, an insertion loss of a light signal may be
reduced. Further, the light signal demultiplexer 600 may be more
readily manufactured because a start point of a light signal does
not need to be precisely controlled.
[0084] According to an example embodiment, the light signal
demultiplexer 600 may demultiplex a light signal that is input
along two or more input light paths. For example, the light signal
demultiplexer 600 may set the fourth output light path 604 to be
the input light path, in addition to the second output light path
602. In such an example, light signals that are output along the
second output light path 602 and the fourth output light path 604
may not need an additional reflector and filter, and thus only a
reflector and filter for light signals that are output along the
first output light path 601 and the third output light path 603 may
be disposed.
[0085] Although the second output light path 602 is set to be the
input light path in FIG. 6, the light signal demultiplexer 600 may
set another output light path to be the input light path. In
addition, an input light path and an output light path of the light
signal demultiplexer 600 may not correspond to each other.
[0086] FIG. 7 is a diagram illustrating a structure of a light
signal demultiplexer 700 in which an output light path does not
correspond to an input light path according to an example
embodiment.
[0087] A plurality of output light paths of the light signal
demultiplexer 700 may not correspond to at least one input light
path. The output light paths of the light signal demultiplexer 700
may be configured independently from the input light path.
Referring to FIG. 7, an input light path 750 may not correspond to
a first output light path 710, a second output light path 720, a
third output light path 730, or a fourth output light path 740.
[0088] The input light path 750 may be set to be in a space present
among the first output light path 710, the second output light path
720, the third output light path 730, and the fourth output light
path 740. For example, the input light path 750 may be set to be in
the middle of the first output light path 710, the second output
light path 720, the third output light path 730, and the fourth
output light path 740. Thus, a deviation in lengths of the output
light paths 710, 720, 730, and 740 of the light signal
demultiplexer 700 may be minimized.
[0089] Alternatively, the input light path 750 may be set to be in
another space that is not present among the output light paths 710,
720, 730, and 740. For example, the input light path 750 may be set
in a left side from the first output light path 710 or in a right
side from the fourth output light path 740. Thus, respective
locations of an input light path and an output light path may be
set independently from one other, and thus the light signal
demultiplexer 700 may be more unrestrictedly designed.
[0090] The units described herein may be implemented using hardware
components and software components. For example, the hardware
components may include microphones, amplifiers, band-pass filters,
audio to digital convertors, non-transitory computer memory and
processing devices. A processing device may be implemented using
one or more general-purpose or special purpose computers, such as,
for example, a processor, a controller and an arithmetic logic
unit, a digital signal processor, a microcomputer, a field
programmable array, a programmable logic unit, a microprocessor or
any other device capable of responding to and executing
instructions in a defined manner. The processing device may run an
operating system (OS) and one or more software applications that
run on the OS. The processing device also may access, store,
manipulate, process, and create data in response to execution of
the software. For purpose of simplicity, the description of a
processing device is used as singular; however, one skilled in the
art will appreciated that a processing device may include multiple
processing elements and multiple types of processing elements. For
example, a processing device may include multiple processors or a
processor and a controller. In addition, different processing
configurations are possible, such a parallel processors.
[0091] The software may include a computer program, a piece of
code, an instruction, or some combination thereof, to independently
or collectively instruct or configure the processing device to
operate as desired. Software and data may be embodied permanently
or temporarily in any type of machine, component, physical or
virtual equipment, computer storage medium or device, or in a
propagated signal wave capable of providing instructions or data to
or being interpreted by the processing device. The software also
may be distributed over network coupled computer systems so that
the software is stored and executed in a distributed fashion. The
software and data may be stored by one or more non-transitory
computer readable recording mediums.
[0092] The methods according to the above-described example
embodiments may be recorded in non-transitory computer-readable
media including program instructions to implement various
operations of the above-described example embodiments. The media
may also include, alone or in combination with the program
instructions, data files, data structures, and the like. The
program instructions recorded on the media may be those specially
designed and constructed for the purposes of example embodiments,
or they may be of the kind well-known and available to those having
skill in the computer software arts. Examples of non-transitory
computer-readable media include magnetic media such as hard disks,
floppy disks, and magnetic tape; optical media such as CD-ROM
discs, DVDs, and/or Blue-ray discs; magneto-optical media such as
optical discs; and hardware devices that are specially configured
to store and perform program instructions, such as read-only memory
(ROM), random access memory (RAM), flash memory (e.g., USB flash
drives, memory cards, memory sticks, etc.), and the like. Examples
of program instructions include both machine code, such as produced
by a compiler, and files containing higher level code that may be
executed by the computer using an interpreter. The above-described
devices may be configured to act as one or more software modules in
order to perform the operations of the above-described example
embodiments, or vice versa.
[0093] While this disclosure includes specific examples, it will be
apparent to one of ordinary skill in the art that various changes
in form and details may be made in these examples without departing
from the spirit and scope of the claims and their equivalents. The
examples described herein are to be considered in a descriptive
sense only, and not for purposes of limitation. Descriptions of
features or aspects in each example are to be considered as being
applicable to similar features or aspects in other examples.
Suitable results may be achieved if the described techniques are
performed in a different order, and/or if components in a described
system, architecture, device, or circuit are combined in a
different manner and/or replaced or supplemented by other
components or their equivalents. Therefore, the scope of the
disclosure is defined not by the detailed description, but by the
claims and their equivalents, and all variations within the scope
of the claims and their equivalents are to be construed as being
included in the disclosure.
* * * * *